Rock-drilling machine



n. A. w. KRAMPITZ. n'ocK DRILLING MACHINE.

APPLICATION FILED FEB. 12. 1920- 1,386,633. Patented Aug. 9, 1921.

a SHEETS-SHEET 1;

' A TTORNEYS mun/Ton R. A. W. KRAMPITZ.

ROCK DRILLING MACHINE.

APPLICATION man FEB- 12. 1920.

3 SHEETS-SHEET 2.

' Patented Aug. 9,

WITNESSES A TTORNEYS w. KRAMPIITZ.

ROCK I mucm I Patented Aug. 9, 1921.

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DRILLING MACHINE.

D FEB. IZI

/ INVENTOR RAM YKI-Um IIZ "Maw/A94 I ATTORNEYS ll Aw WITNESSES v ,UNITEDSTATES ROBERT A. W. KRAMPITZ, F VALDEZ, TERRITORY OF ALASKA.

7 otherwise held against its normal operative 7 application of forcesopposing t 'the certain novel features of the construc- PATENT OFFICE.

ROCK-DRILLING MACHINE.

Specification of Letters Patent.

Application filed February 12, 1920. Serial No. 358,247.

T 0 all whom it may concern Be it known that I, ROBERT A. W. KRAM- Prrz,a citizen of the United States, and a resident of Valdez, Territory ofAlaska, have made certain new and useful Improvements in Rock-DrillingMachines, of which the following is a specification.

My invention relates to rock drilling ma chines.

An important object of my invention is to provide a rock drillingmachine in which movementsand cannot cut its way clear and toautomatically resume and maintain the plower when the reactive eoperative movements of the drill are approximately normal.

Another object isto provide an improved mounting for the drill and itsoperating mechanism well adapted to meet the rigorous requirements ofthis character of work.

Another object is to provide an improved rock drill of simple anddurable construction, "reliable in operation and comparativelyinexpensive in manufacture;

Other objects and advantages reside in tion, arrangement and combinationof parts, which will become apparent as the description proceeds,reference being had to the accompanying drawings forming part of thisspecification, and in which Figure 1 is a sideelevation of myiinprovement. I p

Fig.v 2 is a sectional view on line 22 of Fig. 1.

Fig. 3 is a sectional view on line 33 of Fig.1, looking in thefdirectionof the arrow. p

Fig. 4is a plan v1ew. Fig. 5 is a sectional Fig. 4.

' ig. 6 is a the supporting rods and feed screw being shown in section.i

view on line 5-5 of fragmentary view of the saddle,

Fig. 7 is a detailed view in vertical section of the drill stock anddrillstock bearmg and associated structure."

Fig. 8 is a frontelevation.

Referring to he draw ngs, it will be seen my invention comprises acolumn 10, which may be of any conventional and well known construction.A clamp ll is mounted upon the column 10 and is adapted to be secured inadjusted position on the column by means" of a clamp'screw 12 orthelike. "Integral outwardly and upwardly therefrom is the clamp arm 13and the outer end of the clamp Patented Aug. 9, 1921.

with the clamp member ll 'a n'd extending arm 13 has formedintegrallytherewith a saddle14, as shown in detail in Fig. 6. The saddle14, is provided with spaced longitudinal journals therethrough, asindicated at 15, and these journals preferably lie in the samehorizontal plane; Approximately midway between thejournals andpreferablv a slight distance below the same, the saddle is provided witha longitudinal opening 14' therethrough. The saddle is adapted tosupport the rock drill, as will be hereinafter more fully described.

A main frame 16 the front end immediately to the rear of the has formedat its front end a longitudinal bearing 16' and also at bearing isprovided a depending front frame extensionl'l'. The rear of the mainframe is provided withspaced vertical bearings 18,

the axes of which are 'alined and preferably at right angles to the axisof the longitudinal bearing- 14'. The lower-of the spaced bearings 18has integrally formed therewith a rear depending frame extension 19,which is substantially U-shaped as shown in Fig. 1. A pair of spacedsupporting rods 20 is provided andv each of the supporting rods 20 hasits front end secured in the front frame;

extension 17 and its rear end secured in the rear frame extension 19,the portion-of each rod lying between the front and rear frameextensions being slidably mounted in the journals 15 of the saddle 14.

A swinging auxiliary frame 21 has a vertical bearing 22 disposed betweenthe spaced bearings 18 to, the rear of the main frames 16. The upper endof the auxiliary swing; ing frame21 is provided with spaced horizontalbearings 23.

A crank shaft 24 1s journaled in thebearings 18 of the main frame andthe hearing I 22 of the auxiliary swinging frame and the crank shaft inthis manner serves as the pintle for the auxiliary swinging frame. Thecrank shaft 24 carries at its upper end a driven b vel pinion 25, andits lower end carries a crank disk 26 to which the crank pin 27 issecured. The driven pinion and the crank disk in addition to serving thefunctions to be hereinafter fully described, act to maintain the crankshaft in proper position.

For securing the desired adjustment of the auxiliary swinging frame 21and maintaining the auxiliary frame in this adjustment a worm segment 28is preferably i11- tegrally formed with the bearing 22 of the auxiliaryframe. A worm 29 is journaled in bearing plates 30 which are secured tothe main frame 16 and the squared ends 31 of the worm 29 are adapted tocooperate with an operating tool for effecting the desired adjustment ofthe auxiliary frame. The irreversibility of the worm arrangement effectsthe maintenance of the auxiliary frame in adjusted position.

A drive shaft 32 is journaled in the horizontal bearings 23 of theauxiliary frame and the drive shaft receives its motion from anysuitable source of power not shown, by means of a flexible shaft or atelescopic shaft and universal couplings of conventional construction(not shown). Mounted on the inner end of the drive shaft 22 is a beveldrive pinion 33 having integral therewith a sleeve 34. the inner end ofwhich is provided with 45 degree teeth The driven pinion and its sleeveare loose on the shaft 32, but by virtue of the fact that the drivepinion 88 is in mesh with the driven pinion 25, and that the rear faceof the pinion bears againstthe forward bearing 23, the pinion and itssleeve 34 are prevented from being moved longitudinally with respect tothe drive shaft. A slidable clutch collar 36 is splined to the driveshaft 32 by means of a slot 37 through the shaft and a cross pin 38secured in the collar and extending through the slot, and this clutchcollar is provided with 45 degree teeth as indicated at 39, which areadapted to cooperate with the 45 degree teeth of the sleeve of the drivepinion to normally constrain the drive pinion to motion with the driveshaft. A compression coil spring 40 is mounted on the drive shaft, andhas one end abutting the rear bearing 23 and the other end bearingagainst the slidable collar 36 to maintain the teeth of the collar inengagement with the teeth of the sleeve of the drive frame. It isobvious that unless the resistance to the motion of the drive pinionexceeds the predetermined point (which point may be determined by thestrength and compression under which the coil spring acts) the drivepinion is constrained to rotate with the drive shaft and when thisresistance or load on the drive pinion exceeds this predetermined point,there is a relative slip of the teeth of the collar with respect to theteeth of the sleeve of the drive pinion so that the motion of the driveshaft is not communicated to the drive pinion.

The drill stock 41 is mounted for reciprocatory movement in thelongitudinal hearing 16 of the main frame and this drill stock hasformed at its outer end a drill chuck 42 for receiving the drill tool 43which may be of any conventional construction. The rear end of the drillchuck is provided with axial bore 44 therein of relatively great diameter and an axial bore 45 of reduced 'diameter with respect to theradial bore 44, and which communicates at one end with radial bore Adrill rod 46 has at its inner end a head 47 mounted for a limitedreciproca tory movement in the axial bores 44 and 45. The drill rodthrough the head 47 is of course connected to the drill stock by meansof a cushioned connection consisting of a coil spring 48 disposed in thebore 45 between the inner end of the bore and the head 47 of the drillrod, and a coil spring 49 disposed in the bore 44 between annular plates50. The annular plates 50 as well as the coil spring 49 is mounted onthe drill rod and the inner annular plate abuts against the head 47 ofthe drill rod while the outer annular plates abuts againsta cap 51threaded on the drill stock and provided with a central opening 52through which the drill rod 46 operates. It is apparent that on theforward stroke of the drill rod the spring 48 interposes its resiliencybetween the drill rod and the drill stock and that on the return strokethe spring 49 interposes its resiliency between the drill rod and thedrill stock. The inner endof the drill rod 46 is connected preferably bymeans of a threaded shank socket connection to the cross head 54, whichin turn is connected by the connecting rod 55 with the crank pin 27 ofthe crank disk 26.

Common means are provided for feeding the drill and for imparting thedesired turning movements to the drilling tool, and consists of a feedshaft 56 having its front end rotatably mounted in the frame extension18, and its rear end rotatably mounted in the frame extension 19 andcarrying intermediate said frame sections a feed screw 57; the feedscrew 57 extends through the opening 14 of the saddle and cooperateswith a nut 58 fixed to the saddle and having it opening alined with theopening 14. A hand crank 59 is provided for imparting the desiredmovement to the feed screw 57. The end of the feed shaft adjacent to theframe extension 17 and gear wheel 60 is 1 jections 62 mounted inlongitudinal slots 63 61, while permitting relative rectilinear moformedin the drill'stock 41' to constrain the drill stock to rotary motionwiththe gear tion of the drill stock with relation to the gear wheel 61.The "gear wheel 61 is constrained against rectilinear motion by; beingmounted between the front frame extension 1 1'7 and a depending annularcollar abutment 63, preferably formed integral with themain frame, whichis internally threaded as shown. A bushing 64 is threaded in saidannular collar and its inner end adj ustably abuts the'gear wheel 61, asshown in Fig. 7 The gear wheels'60 and 61 are pref erably s0proportionedthat for every turn thedrill stock is turned i ating partspartaklng ofmovements of rela- 85 being effectively isolated are guardedwhile of the feed screw twice.

In practice the saddle having been secured in desired positionby meansof the clamp and column and power applied to the drive shaft 32, motionis transmitted through the drive pinion 33, driven pinion 25, crankshaft 24, crank disk 26, and its pin 27 to the connecting rod 55 whichimparts reciprocatory motion to the drill rod 46. Drill rod 46 throughits cushioned connection imparts reciprocatory motion to the drill stock41 and consequently to the drill tool 43. The hand crank59is turned asdesired to ad- Vance or feed the entire main frame and consequently thedrilling tool and this automatically effects the turning movement of thedrill tool as heretofore described.

If the drilling tool becomes jammed,

* caught or is otherwise held against its normal operative movement andcannot cut its way clear, the power applied through the drive shaft 32would,if communicated positively, set up destructive stresses in thedrilling tool and its associated mechanism tending to rupture or distortthe same, but in the present invention this does not occur as when thedrill is caught or jammed the reactive force to the operative movementsof the drill is of course greatly increased and this results in agreater resistanceof load of motion of the drive pinion 33 with theconsequent relative slip or movement between the teeth of the sleeve ofthe drive pinion and the teeth of the clutch collar, and motion is notthen communicated to the drive pinion and therefore the drilling tool isnotforced to partake of reciprocatory motion while so jammed, caught orheld that a forced reciprocation would involve destruction, breakage,rupture, or dis tortion of the drilling tool or its operating mechanismor associated structure. Consequently it is impossible for the stressesin' a predetermined point which point is of course established withinthe ran e of stress that the several parts are adapte to bear.

Moreover, asthe crank shaft 24 constitutes the axis J of swing of theauxiliary frame, the driven pinion 25 has its axis lying in the axis ofthe crankshaft and the drive shaft 32 and its pinion 33-are carried onthe auxiliary frameito swingfabout the crank shaftas its axis, thepinions 25 and 33 mesh: ing in all positions of the auxiliary frame withrespect to the main. frame and power may be tranmnitted thereto andtherefore to the drilling tool irrespectiveof the location of the sourceof power with respect to said main frame; I

,Again, thejmain frame, frame extension,-

supporting rods, saddle,etc. define a substantially inclosed space inwhich the opertively large amplitude function and which beingimmediately accessible for purposes of adjustment, repair, etc.Furthermore, this particular mounting gives not only great strength, andan adaptability for ready and easy adjustment, but also a high degree ofbalance.

I claim 1; A rock drill of the character described comprising amainframe having a' longitudinal bearing at its forward end and spaced 2. Arock drill of the character described comprising a main frame havingspaced and a worm mounted upon said main frame in mesh with said wormsegment, all as and for the purposes set forth.

3. In a rock drill of the character described, a drilling tool, meansfor reciprocat ing said drilling tool, a drive shaft, a drive pinion 1for actuating said reciprocatory means having a sleeve provided at itsouter end with teeth and loosely mounted on said drive shaft, a slidablecollar splined on said drive shaft and. having one end provided withteeth adapted to be engaged with the teeth of said drive pinion sleevefor nor mally constraining said drive pinion to motion with said driveshaft and permitting motion of said drive shaft relative to said drivepinion when the resistance to the reciprocation of said drilling toolexceeds a predetermined point, and a spring for maintaining the teeth ofsaid collar in engagement with the teeth of said pinion.

4:. In a rock drill of the character described, a drill stock having anaxial bore at its inner end, a drill rod having a head adapted tooperate in said bore and a cushioning connection between said drill rodand said drill stock including a coil spring between said drill rod headand the inner end of said bore, an annular plate disposed against theouter face of said drill rod head, a cap closing the outer end of saidbore and a coil spring between said plate and said cap, all as and forthe purposes set forth.

5. A rock drill of the character described comprising a support providedwith spaced journals therein, a. main frame having a longitudinalbearing on the under side of its forward portion and having a dependingfront extension below said longitudinal bearings and a depending rearextension of U-shaped form, spaced supporting rods fixed to said frontframe extension and to the lower leg of the rear U-shaped extension andcarried by the journals of said support, a drill stock mounted forreciprocatory movement in such longitudinal bearing, and means forreciprocating said drill stock, including a crank mechanism operating between the legs of the U-shaped extension and a connecting rod lyingbelow said main frame and above the lower end of the frame extension inall phases of its movements.

ROBERT A. \V. KR-AMPITZ.

